Interesting mounting style. How would you compare this mount to integrated plate mount? From what I see, the plate with pin mount will lie on the bottom case, so it should be kind of stiff?
So where this differs is the recommended materials for the plate. The nylon or pp plates should be much more flexible than metallic or hard plastic plates. Add to that the loose mounting style, and you should get more flex and uniform flex across the board. Now this isn't a gasket/isolation mount, so I wouldn't expect to get as much flex as one of those, it's more the uniform flex across the whole board which is interesting (imagine a net stretched taught, suspended between 4 trees at the corners, with keys on it).
If you used the provided files to create a metallic plate it would be similar to an integrated plate mount, but since the integrated mount is sandwiched/screwed in, the metallic on this would still provide more flex, since it's still loose and just "draped" over the 4 pins.
Hope that helps a little, and I'm sure OP will correct me if wrong
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